Mitral Valve Repair

Mitral valve repair is an open heart procedure performed by cardiothoracic surgeons to treat stenosis (narrowing) or regurgitation (leakage) of the mitral valve. The mitral valve is the "inflow valve" for the left side of the heart. Blood flows from the lungs, where it picks up oxygen, and into the left atrium. When it opens, the mitral valve allows blood to flow from the left atrium to the heart's main pumping chamber called the left ventricle. It then closes to keep blood from leaking back into the lungs when the ventricle contracts (squeezes) to push blood out to the body. It has two flaps, or leaflets.

Occasionally, the mitral valve is abnormal from birth (congenital). More often the mitral valve becomes abnormal with age (degenerative) or as a result of rheumatic fever. In rare instances the mitral valve can be destroyed by infection or a bacterial endocarditis. Mitral regurgitation may also occur as a result of ischemic heart disease (coronary artery disease).

Often the mitral valve is so damaged that it must be replaced (refer to Mitral Valve Replacement). Occasionally, however, the valve can be repaired rather than replaced. One type of repair is a procedure called mitral commissurotomy. Mitral commissurotomy can be performed for some valves that are narrow or "stenotic" either from birth or from damage by rheumatic fever. Most often today, rheumatic mitral stenosis is treated by balloon valvuloplasty, a procedure performed in the cardiac catheterization laboratory by interventional cardiologists. Using a catheter with a balloon on the end, the balloon is expanded inside the valve "stretching" it open.

More often mitral valve repair is performed to correct a leaking or regurgitant valve. Congenital mitral regurgitation may be due to a cleft mitral valve (a valve with a separation or cleft down the middle) associated with an atrial septal defect, a type of hole in the heart between the low pressure chambers or atria. Such valves can sometimes be repaired simply by closing the cleft with sutures. Valves regurgitant due to bacterial endocarditis can occasionally be repaired, however the majority of mitral valve repairs are performed for degenerative disease. Degenerative mitral valve disease may be due to an elongation or rupture of the chordal apparatus, the "heart-strings" that support the valve normally, or due to a more generalized weakness of the valve itself such as the "floppy valve" syndrome in which all of the components of the valve are enlarged and elongated.

Not all mitral valves can be repaired. A preoperative echocardiogram may help your surgeon predict the likelihood of repair, but cannot guarantee it. Mitral valves that are regurgitant due to rheumatic fever are often both stenotic and regurgitant, and are often beyond repair.